The subject matter disclosed herein relates generally to thermal equipment, and more particularly to inhibition of high temperature corrosion thereof.
Thermal equipment, such as boilers, diesel engines, gas turbines, furnaces, and process reactors may be used to burn certain liquid fuels. In such equipment, the fuels may contain traces of metallic contaminants such as vanadium, sodium, potassium, calcium, and lead that need to be treated prior to their combustion in order to attenuate the high temperature corrosion effects of these metals on thermal equipment. The metallic salts contained in the fuels are water soluble and may be extracted upstream of the thermal equipment. For example, fuel washing operations with water, followed by water/fuel separation with the aid of electrostatic separators or centrifuges, are commonly implemented to separate water soluble metallic salts such as chlorides and sulfates of sodium, potassium and partially calcium. However, the vanadium derivatives contained in the fuels are organic in nature and are not water soluble and therefore cannot be extracted by such a washing operation. The presence of such organic compounds of vanadium in liquid fuels burned in the thermal equipment is likely to cause high temperature corrosion of the metallic materials in contact with the combustion gases.